Conductive compositions have been developed for various purposes including facilitating electrostatic discharge and as a current transfer medium on printed circuit boards. Recently, conductive compositions have been used, instead of conventional wires, as part of an electrical system for conducting current from a power source to various current operated circuit components on a variety of objects such as wearing apparel, children's toys and books.
Examples of desirable electrical systems that use conductive compositions are disclosed in U.S. Pat. Nos. 5,455,749 and 5,626,948. The '749 patent discloses electrical systems that include a power source, one or more circuit components such as an LED or a sound chip, and conductive composition for connecting the power source to the circuit components so that current generated by the power supply can be delivered to such circuit components. In one embodiment, the conductive composition may be colored. In another embodiment, the conductive composition may form at least a portion of a design arranged on an object. In yet another embodiment, the conductive composition is sufficiently durable to withstand multiple washes without cracking, substantial resistance build up or other failure.
The '948 patent also discloses the use of conductive compositions as part of an electrical system on toys, clothing and other articles. It is particularly directed toward a "vertically conductive" composition that forms part of an electrical system where current is permitted to flow in a direction normal to the surface of an object on which the conductive composition is arranged, but is not permitted to flow through and along the conductive composition in a direction parallel to the surface of the article on which the conductive composition is arranged. The vertically conductive composition of the '948 patent is particularly useful where colored conductive compositions are desired.
Although various efforts have been made to develop conductive compositions that can be used as part of an electrical system for consumer and industrial products, the prior art does not disclose, teach or suggest in any way that such conductive compositions can be used as part of a switch for fabric articles where such conductive composition is arranged in registration with a design on the surface of the fabric article. The present invention addresses the aforementioned shortcomings and needs of the prior art.